This is a proposal to examine short-term memory for speech and its development in childhood. The research is based on the premise that an analytic understanding of memory for speech requires a distinction between passive processes that occur automatically (e.g., auditory sensory and phonological memories and their decay) and active processes that can be initiated and/or carried out only with at least some minimal allocation of attention (e.g., attentive encoding of speech; overt or covert articulation). The main goal of the research is to disentangle these types of memory faculty and to determine how each of them develops. To this end, there are three specific aims: (1) To examine developmental changes in the rate of auditory memory decay; (2) To examine developmental changes in how spoken utterances are temporarily retained if the utterances are ignored at the time of their presentation (e.g., changes in which items are retained, for how long they are retained, or with what forms of coding they are retained); and (3) To determine the contributions of passive, auditory and phonological memory decay vs. active, articulatory processes in immediate memory tasks and their development. Research addressing each of these aims is based on a different method. In the examination of auditory memory decay, subjects compare two slightly different sounds separated by a variable interval during which memory of the first sound can decay. In the examination of ignored speech, subjects are to ignore monosyllabic, spoken words while engaging in the silent processing of visual materials. Occasionally, there is a cue for the subject to interrupt the visual task and identify one or more of the most recent syllables that had been ignored. Last, the examination of passive decay and active processing involves an immediate, serial memory task in which the delay between the to-be-recalled list and the time of recall of each item is measured and related to the amount of speech memory decay that occurred. In all three procedures, there is an emphasis on testing subjects of different ages at similar levels of performance so that forgetting rates can be compared. It is clear that memory of the auditory and phonological qualities of speech are affected in important ways by a wide range of language-related disabilities, but little is known about the memory mechanisms involved or their normal development. The present research helps to fill these gaps.